ORGANIC-ACID EXCRETION BY HELMINTHS

The excretion of lactic, succinic acetic, propionic and other fatty acids is a characteristic of parasitic helminths. It appears that, although many parasites occupy environments in which oxygen is available, fermentation pathways are preferred. Many suggestions have been put forward to explain this apparent anomaly, yet none so far has proved satisfactory. Explanations have involved analysis of the properties of the acids themselves, and proposals that physico-chemical characteristics of the parasite environment other than oxygen ore the important determinants of metabolism. Recent research suggests that even the immune mechanisms of the host may play on important role. Here, Chris Bryant takes a look at the mystery of organic excretion by helminths.